Incandescent light bulbs are commonly used for indicator lamps, task lamps, general lighting, decorative lamps, warning lamps, traffic lamps and the like. However, incandescent bulbs are generally inefficient in terms of energy use and subject to frequent replacement due to their limited lifetime. Significant savings can be made by the use light bulbs wherein the source of light is from light emitting diodes (LED). LEDs consume a fraction of the energy used to illuminate incandescent bulbs and last much longer.
The problem with LEDs, without special light dissipating optics, is that the light intensity varies as a function of viewing angle. As shown in FIG. 1, the maximum light intensity is generally observed when the viewing angle is 0.degree. or head-on and the least at 90.degree. or when you view the device from the side. Thus, light bulbs made from LEDs of this type have the problem of being viewed with sufficient intensity at various viewing angles other than head-on.
U.S. Pat. No. 5,561,346 to Byrnes is directed to a lamp comprising a plurality of LEDs extending from opposed rounded surfaces to project light radially about the lamp. The patent requires special reflecting optics for projecting the light 360.degree. around the lamp.
Accordingly, it is an object of this invention to provide an LED light bulb that can be viewed from various viewing angles wherein the light intensity is constant without the need for special light dissipating optics or special light reflecting optics.